1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright(c) 2013 - 2018 Intel Corporation. */ 3 4 #include <linux/bitfield.h> 5 #include <linux/prefetch.h> 6 7 #include "iavf.h" 8 #include "iavf_trace.h" 9 #include "iavf_prototype.h" 10 11 static __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size, 12 u32 td_tag) 13 { 14 return cpu_to_le64(IAVF_TX_DESC_DTYPE_DATA | 15 ((u64)td_cmd << IAVF_TXD_QW1_CMD_SHIFT) | 16 ((u64)td_offset << IAVF_TXD_QW1_OFFSET_SHIFT) | 17 ((u64)size << IAVF_TXD_QW1_TX_BUF_SZ_SHIFT) | 18 ((u64)td_tag << IAVF_TXD_QW1_L2TAG1_SHIFT)); 19 } 20 21 #define IAVF_TXD_CMD (IAVF_TX_DESC_CMD_EOP | IAVF_TX_DESC_CMD_RS) 22 23 /** 24 * iavf_unmap_and_free_tx_resource - Release a Tx buffer 25 * @ring: the ring that owns the buffer 26 * @tx_buffer: the buffer to free 27 **/ 28 static void iavf_unmap_and_free_tx_resource(struct iavf_ring *ring, 29 struct iavf_tx_buffer *tx_buffer) 30 { 31 if (tx_buffer->skb) { 32 if (tx_buffer->tx_flags & IAVF_TX_FLAGS_FD_SB) 33 kfree(tx_buffer->raw_buf); 34 else 35 dev_kfree_skb_any(tx_buffer->skb); 36 if (dma_unmap_len(tx_buffer, len)) 37 dma_unmap_single(ring->dev, 38 dma_unmap_addr(tx_buffer, dma), 39 dma_unmap_len(tx_buffer, len), 40 DMA_TO_DEVICE); 41 } else if (dma_unmap_len(tx_buffer, len)) { 42 dma_unmap_page(ring->dev, 43 dma_unmap_addr(tx_buffer, dma), 44 dma_unmap_len(tx_buffer, len), 45 DMA_TO_DEVICE); 46 } 47 48 tx_buffer->next_to_watch = NULL; 49 tx_buffer->skb = NULL; 50 dma_unmap_len_set(tx_buffer, len, 0); 51 /* tx_buffer must be completely set up in the transmit path */ 52 } 53 54 /** 55 * iavf_clean_tx_ring - Free any empty Tx buffers 56 * @tx_ring: ring to be cleaned 57 **/ 58 static void iavf_clean_tx_ring(struct iavf_ring *tx_ring) 59 { 60 unsigned long bi_size; 61 u16 i; 62 63 /* ring already cleared, nothing to do */ 64 if (!tx_ring->tx_bi) 65 return; 66 67 /* Free all the Tx ring sk_buffs */ 68 for (i = 0; i < tx_ring->count; i++) 69 iavf_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]); 70 71 bi_size = sizeof(struct iavf_tx_buffer) * tx_ring->count; 72 memset(tx_ring->tx_bi, 0, bi_size); 73 74 /* Zero out the descriptor ring */ 75 memset(tx_ring->desc, 0, tx_ring->size); 76 77 tx_ring->next_to_use = 0; 78 tx_ring->next_to_clean = 0; 79 80 if (!tx_ring->netdev) 81 return; 82 83 /* cleanup Tx queue statistics */ 84 netdev_tx_reset_queue(txring_txq(tx_ring)); 85 } 86 87 /** 88 * iavf_free_tx_resources - Free Tx resources per queue 89 * @tx_ring: Tx descriptor ring for a specific queue 90 * 91 * Free all transmit software resources 92 **/ 93 void iavf_free_tx_resources(struct iavf_ring *tx_ring) 94 { 95 iavf_clean_tx_ring(tx_ring); 96 kfree(tx_ring->tx_bi); 97 tx_ring->tx_bi = NULL; 98 99 if (tx_ring->desc) { 100 dma_free_coherent(tx_ring->dev, tx_ring->size, 101 tx_ring->desc, tx_ring->dma); 102 tx_ring->desc = NULL; 103 } 104 } 105 106 /** 107 * iavf_get_tx_pending - how many Tx descriptors not processed 108 * @ring: the ring of descriptors 109 * @in_sw: is tx_pending being checked in SW or HW 110 * 111 * Since there is no access to the ring head register 112 * in XL710, we need to use our local copies 113 **/ 114 static u32 iavf_get_tx_pending(struct iavf_ring *ring, bool in_sw) 115 { 116 u32 head, tail; 117 118 /* underlying hardware might not allow access and/or always return 119 * 0 for the head/tail registers so just use the cached values 120 */ 121 head = ring->next_to_clean; 122 tail = ring->next_to_use; 123 124 if (head != tail) 125 return (head < tail) ? 126 tail - head : (tail + ring->count - head); 127 128 return 0; 129 } 130 131 /** 132 * iavf_force_wb - Issue SW Interrupt so HW does a wb 133 * @vsi: the VSI we care about 134 * @q_vector: the vector on which to force writeback 135 **/ 136 static void iavf_force_wb(struct iavf_vsi *vsi, struct iavf_q_vector *q_vector) 137 { 138 u32 val = IAVF_VFINT_DYN_CTLN1_INTENA_MASK | 139 IAVF_VFINT_DYN_CTLN1_ITR_INDX_MASK | /* set noitr */ 140 IAVF_VFINT_DYN_CTLN1_SWINT_TRIG_MASK | 141 IAVF_VFINT_DYN_CTLN1_SW_ITR_INDX_ENA_MASK 142 /* allow 00 to be written to the index */; 143 144 wr32(&vsi->back->hw, 145 IAVF_VFINT_DYN_CTLN1(q_vector->reg_idx), 146 val); 147 } 148 149 /** 150 * iavf_detect_recover_hung - Function to detect and recover hung_queues 151 * @vsi: pointer to vsi struct with tx queues 152 * 153 * VSI has netdev and netdev has TX queues. This function is to check each of 154 * those TX queues if they are hung, trigger recovery by issuing SW interrupt. 155 **/ 156 void iavf_detect_recover_hung(struct iavf_vsi *vsi) 157 { 158 struct iavf_ring *tx_ring = NULL; 159 struct net_device *netdev; 160 unsigned int i; 161 int packets; 162 163 if (!vsi) 164 return; 165 166 if (test_bit(__IAVF_VSI_DOWN, vsi->state)) 167 return; 168 169 netdev = vsi->netdev; 170 if (!netdev) 171 return; 172 173 if (!netif_carrier_ok(netdev)) 174 return; 175 176 for (i = 0; i < vsi->back->num_active_queues; i++) { 177 tx_ring = &vsi->back->tx_rings[i]; 178 if (tx_ring && tx_ring->desc) { 179 /* If packet counter has not changed the queue is 180 * likely stalled, so force an interrupt for this 181 * queue. 182 * 183 * prev_pkt_ctr would be negative if there was no 184 * pending work. 185 */ 186 packets = tx_ring->stats.packets & INT_MAX; 187 if (tx_ring->tx_stats.prev_pkt_ctr == packets) { 188 iavf_force_wb(vsi, tx_ring->q_vector); 189 continue; 190 } 191 192 /* Memory barrier between read of packet count and call 193 * to iavf_get_tx_pending() 194 */ 195 smp_rmb(); 196 tx_ring->tx_stats.prev_pkt_ctr = 197 iavf_get_tx_pending(tx_ring, true) ? packets : -1; 198 } 199 } 200 } 201 202 #define WB_STRIDE 4 203 204 /** 205 * iavf_clean_tx_irq - Reclaim resources after transmit completes 206 * @vsi: the VSI we care about 207 * @tx_ring: Tx ring to clean 208 * @napi_budget: Used to determine if we are in netpoll 209 * 210 * Returns true if there's any budget left (e.g. the clean is finished) 211 **/ 212 static bool iavf_clean_tx_irq(struct iavf_vsi *vsi, 213 struct iavf_ring *tx_ring, int napi_budget) 214 { 215 int i = tx_ring->next_to_clean; 216 struct iavf_tx_buffer *tx_buf; 217 struct iavf_tx_desc *tx_desc; 218 unsigned int total_bytes = 0, total_packets = 0; 219 unsigned int budget = IAVF_DEFAULT_IRQ_WORK; 220 221 tx_buf = &tx_ring->tx_bi[i]; 222 tx_desc = IAVF_TX_DESC(tx_ring, i); 223 i -= tx_ring->count; 224 225 do { 226 struct iavf_tx_desc *eop_desc = tx_buf->next_to_watch; 227 228 /* if next_to_watch is not set then there is no work pending */ 229 if (!eop_desc) 230 break; 231 232 /* prevent any other reads prior to eop_desc */ 233 smp_rmb(); 234 235 iavf_trace(clean_tx_irq, tx_ring, tx_desc, tx_buf); 236 /* if the descriptor isn't done, no work yet to do */ 237 if (!(eop_desc->cmd_type_offset_bsz & 238 cpu_to_le64(IAVF_TX_DESC_DTYPE_DESC_DONE))) 239 break; 240 241 /* clear next_to_watch to prevent false hangs */ 242 tx_buf->next_to_watch = NULL; 243 244 /* update the statistics for this packet */ 245 total_bytes += tx_buf->bytecount; 246 total_packets += tx_buf->gso_segs; 247 248 /* free the skb */ 249 napi_consume_skb(tx_buf->skb, napi_budget); 250 251 /* unmap skb header data */ 252 dma_unmap_single(tx_ring->dev, 253 dma_unmap_addr(tx_buf, dma), 254 dma_unmap_len(tx_buf, len), 255 DMA_TO_DEVICE); 256 257 /* clear tx_buffer data */ 258 tx_buf->skb = NULL; 259 dma_unmap_len_set(tx_buf, len, 0); 260 261 /* unmap remaining buffers */ 262 while (tx_desc != eop_desc) { 263 iavf_trace(clean_tx_irq_unmap, 264 tx_ring, tx_desc, tx_buf); 265 266 tx_buf++; 267 tx_desc++; 268 i++; 269 if (unlikely(!i)) { 270 i -= tx_ring->count; 271 tx_buf = tx_ring->tx_bi; 272 tx_desc = IAVF_TX_DESC(tx_ring, 0); 273 } 274 275 /* unmap any remaining paged data */ 276 if (dma_unmap_len(tx_buf, len)) { 277 dma_unmap_page(tx_ring->dev, 278 dma_unmap_addr(tx_buf, dma), 279 dma_unmap_len(tx_buf, len), 280 DMA_TO_DEVICE); 281 dma_unmap_len_set(tx_buf, len, 0); 282 } 283 } 284 285 /* move us one more past the eop_desc for start of next pkt */ 286 tx_buf++; 287 tx_desc++; 288 i++; 289 if (unlikely(!i)) { 290 i -= tx_ring->count; 291 tx_buf = tx_ring->tx_bi; 292 tx_desc = IAVF_TX_DESC(tx_ring, 0); 293 } 294 295 prefetch(tx_desc); 296 297 /* update budget accounting */ 298 budget--; 299 } while (likely(budget)); 300 301 i += tx_ring->count; 302 tx_ring->next_to_clean = i; 303 u64_stats_update_begin(&tx_ring->syncp); 304 tx_ring->stats.bytes += total_bytes; 305 tx_ring->stats.packets += total_packets; 306 u64_stats_update_end(&tx_ring->syncp); 307 tx_ring->q_vector->tx.total_bytes += total_bytes; 308 tx_ring->q_vector->tx.total_packets += total_packets; 309 310 if (tx_ring->flags & IAVF_TXR_FLAGS_WB_ON_ITR) { 311 /* check to see if there are < 4 descriptors 312 * waiting to be written back, then kick the hardware to force 313 * them to be written back in case we stay in NAPI. 314 * In this mode on X722 we do not enable Interrupt. 315 */ 316 unsigned int j = iavf_get_tx_pending(tx_ring, false); 317 318 if (budget && 319 ((j / WB_STRIDE) == 0) && (j > 0) && 320 !test_bit(__IAVF_VSI_DOWN, vsi->state) && 321 (IAVF_DESC_UNUSED(tx_ring) != tx_ring->count)) 322 tx_ring->arm_wb = true; 323 } 324 325 /* notify netdev of completed buffers */ 326 netdev_tx_completed_queue(txring_txq(tx_ring), 327 total_packets, total_bytes); 328 329 #define TX_WAKE_THRESHOLD ((s16)(DESC_NEEDED * 2)) 330 if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) && 331 (IAVF_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) { 332 /* Make sure that anybody stopping the queue after this 333 * sees the new next_to_clean. 334 */ 335 smp_mb(); 336 if (__netif_subqueue_stopped(tx_ring->netdev, 337 tx_ring->queue_index) && 338 !test_bit(__IAVF_VSI_DOWN, vsi->state)) { 339 netif_wake_subqueue(tx_ring->netdev, 340 tx_ring->queue_index); 341 ++tx_ring->tx_stats.restart_queue; 342 } 343 } 344 345 return !!budget; 346 } 347 348 /** 349 * iavf_enable_wb_on_itr - Arm hardware to do a wb, interrupts are not enabled 350 * @vsi: the VSI we care about 351 * @q_vector: the vector on which to enable writeback 352 * 353 **/ 354 static void iavf_enable_wb_on_itr(struct iavf_vsi *vsi, 355 struct iavf_q_vector *q_vector) 356 { 357 u16 flags = q_vector->tx.ring[0].flags; 358 u32 val; 359 360 if (!(flags & IAVF_TXR_FLAGS_WB_ON_ITR)) 361 return; 362 363 if (q_vector->arm_wb_state) 364 return; 365 366 val = IAVF_VFINT_DYN_CTLN1_WB_ON_ITR_MASK | 367 IAVF_VFINT_DYN_CTLN1_ITR_INDX_MASK; /* set noitr */ 368 369 wr32(&vsi->back->hw, 370 IAVF_VFINT_DYN_CTLN1(q_vector->reg_idx), val); 371 q_vector->arm_wb_state = true; 372 } 373 374 static bool iavf_container_is_rx(struct iavf_q_vector *q_vector, 375 struct iavf_ring_container *rc) 376 { 377 return &q_vector->rx == rc; 378 } 379 380 #define IAVF_AIM_MULTIPLIER_100G 2560 381 #define IAVF_AIM_MULTIPLIER_50G 1280 382 #define IAVF_AIM_MULTIPLIER_40G 1024 383 #define IAVF_AIM_MULTIPLIER_20G 512 384 #define IAVF_AIM_MULTIPLIER_10G 256 385 #define IAVF_AIM_MULTIPLIER_1G 32 386 387 static unsigned int iavf_mbps_itr_multiplier(u32 speed_mbps) 388 { 389 switch (speed_mbps) { 390 case SPEED_100000: 391 return IAVF_AIM_MULTIPLIER_100G; 392 case SPEED_50000: 393 return IAVF_AIM_MULTIPLIER_50G; 394 case SPEED_40000: 395 return IAVF_AIM_MULTIPLIER_40G; 396 case SPEED_25000: 397 case SPEED_20000: 398 return IAVF_AIM_MULTIPLIER_20G; 399 case SPEED_10000: 400 default: 401 return IAVF_AIM_MULTIPLIER_10G; 402 case SPEED_1000: 403 case SPEED_100: 404 return IAVF_AIM_MULTIPLIER_1G; 405 } 406 } 407 408 static unsigned int 409 iavf_virtchnl_itr_multiplier(enum virtchnl_link_speed speed_virtchnl) 410 { 411 switch (speed_virtchnl) { 412 case VIRTCHNL_LINK_SPEED_40GB: 413 return IAVF_AIM_MULTIPLIER_40G; 414 case VIRTCHNL_LINK_SPEED_25GB: 415 case VIRTCHNL_LINK_SPEED_20GB: 416 return IAVF_AIM_MULTIPLIER_20G; 417 case VIRTCHNL_LINK_SPEED_10GB: 418 default: 419 return IAVF_AIM_MULTIPLIER_10G; 420 case VIRTCHNL_LINK_SPEED_1GB: 421 case VIRTCHNL_LINK_SPEED_100MB: 422 return IAVF_AIM_MULTIPLIER_1G; 423 } 424 } 425 426 static unsigned int iavf_itr_divisor(struct iavf_adapter *adapter) 427 { 428 if (ADV_LINK_SUPPORT(adapter)) 429 return IAVF_ITR_ADAPTIVE_MIN_INC * 430 iavf_mbps_itr_multiplier(adapter->link_speed_mbps); 431 else 432 return IAVF_ITR_ADAPTIVE_MIN_INC * 433 iavf_virtchnl_itr_multiplier(adapter->link_speed); 434 } 435 436 /** 437 * iavf_update_itr - update the dynamic ITR value based on statistics 438 * @q_vector: structure containing interrupt and ring information 439 * @rc: structure containing ring performance data 440 * 441 * Stores a new ITR value based on packets and byte 442 * counts during the last interrupt. The advantage of per interrupt 443 * computation is faster updates and more accurate ITR for the current 444 * traffic pattern. Constants in this function were computed 445 * based on theoretical maximum wire speed and thresholds were set based 446 * on testing data as well as attempting to minimize response time 447 * while increasing bulk throughput. 448 **/ 449 static void iavf_update_itr(struct iavf_q_vector *q_vector, 450 struct iavf_ring_container *rc) 451 { 452 unsigned int avg_wire_size, packets, bytes, itr; 453 unsigned long next_update = jiffies; 454 455 /* If we don't have any rings just leave ourselves set for maximum 456 * possible latency so we take ourselves out of the equation. 457 */ 458 if (!rc->ring || !ITR_IS_DYNAMIC(rc->ring->itr_setting)) 459 return; 460 461 /* For Rx we want to push the delay up and default to low latency. 462 * for Tx we want to pull the delay down and default to high latency. 463 */ 464 itr = iavf_container_is_rx(q_vector, rc) ? 465 IAVF_ITR_ADAPTIVE_MIN_USECS | IAVF_ITR_ADAPTIVE_LATENCY : 466 IAVF_ITR_ADAPTIVE_MAX_USECS | IAVF_ITR_ADAPTIVE_LATENCY; 467 468 /* If we didn't update within up to 1 - 2 jiffies we can assume 469 * that either packets are coming in so slow there hasn't been 470 * any work, or that there is so much work that NAPI is dealing 471 * with interrupt moderation and we don't need to do anything. 472 */ 473 if (time_after(next_update, rc->next_update)) 474 goto clear_counts; 475 476 /* If itr_countdown is set it means we programmed an ITR within 477 * the last 4 interrupt cycles. This has a side effect of us 478 * potentially firing an early interrupt. In order to work around 479 * this we need to throw out any data received for a few 480 * interrupts following the update. 481 */ 482 if (q_vector->itr_countdown) { 483 itr = rc->target_itr; 484 goto clear_counts; 485 } 486 487 packets = rc->total_packets; 488 bytes = rc->total_bytes; 489 490 if (iavf_container_is_rx(q_vector, rc)) { 491 /* If Rx there are 1 to 4 packets and bytes are less than 492 * 9000 assume insufficient data to use bulk rate limiting 493 * approach unless Tx is already in bulk rate limiting. We 494 * are likely latency driven. 495 */ 496 if (packets && packets < 4 && bytes < 9000 && 497 (q_vector->tx.target_itr & IAVF_ITR_ADAPTIVE_LATENCY)) { 498 itr = IAVF_ITR_ADAPTIVE_LATENCY; 499 goto adjust_by_size; 500 } 501 } else if (packets < 4) { 502 /* If we have Tx and Rx ITR maxed and Tx ITR is running in 503 * bulk mode and we are receiving 4 or fewer packets just 504 * reset the ITR_ADAPTIVE_LATENCY bit for latency mode so 505 * that the Rx can relax. 506 */ 507 if (rc->target_itr == IAVF_ITR_ADAPTIVE_MAX_USECS && 508 (q_vector->rx.target_itr & IAVF_ITR_MASK) == 509 IAVF_ITR_ADAPTIVE_MAX_USECS) 510 goto clear_counts; 511 } else if (packets > 32) { 512 /* If we have processed over 32 packets in a single interrupt 513 * for Tx assume we need to switch over to "bulk" mode. 514 */ 515 rc->target_itr &= ~IAVF_ITR_ADAPTIVE_LATENCY; 516 } 517 518 /* We have no packets to actually measure against. This means 519 * either one of the other queues on this vector is active or 520 * we are a Tx queue doing TSO with too high of an interrupt rate. 521 * 522 * Between 4 and 56 we can assume that our current interrupt delay 523 * is only slightly too low. As such we should increase it by a small 524 * fixed amount. 525 */ 526 if (packets < 56) { 527 itr = rc->target_itr + IAVF_ITR_ADAPTIVE_MIN_INC; 528 if ((itr & IAVF_ITR_MASK) > IAVF_ITR_ADAPTIVE_MAX_USECS) { 529 itr &= IAVF_ITR_ADAPTIVE_LATENCY; 530 itr += IAVF_ITR_ADAPTIVE_MAX_USECS; 531 } 532 goto clear_counts; 533 } 534 535 if (packets <= 256) { 536 itr = min(q_vector->tx.current_itr, q_vector->rx.current_itr); 537 itr &= IAVF_ITR_MASK; 538 539 /* Between 56 and 112 is our "goldilocks" zone where we are 540 * working out "just right". Just report that our current 541 * ITR is good for us. 542 */ 543 if (packets <= 112) 544 goto clear_counts; 545 546 /* If packet count is 128 or greater we are likely looking 547 * at a slight overrun of the delay we want. Try halving 548 * our delay to see if that will cut the number of packets 549 * in half per interrupt. 550 */ 551 itr /= 2; 552 itr &= IAVF_ITR_MASK; 553 if (itr < IAVF_ITR_ADAPTIVE_MIN_USECS) 554 itr = IAVF_ITR_ADAPTIVE_MIN_USECS; 555 556 goto clear_counts; 557 } 558 559 /* The paths below assume we are dealing with a bulk ITR since 560 * number of packets is greater than 256. We are just going to have 561 * to compute a value and try to bring the count under control, 562 * though for smaller packet sizes there isn't much we can do as 563 * NAPI polling will likely be kicking in sooner rather than later. 564 */ 565 itr = IAVF_ITR_ADAPTIVE_BULK; 566 567 adjust_by_size: 568 /* If packet counts are 256 or greater we can assume we have a gross 569 * overestimation of what the rate should be. Instead of trying to fine 570 * tune it just use the formula below to try and dial in an exact value 571 * give the current packet size of the frame. 572 */ 573 avg_wire_size = bytes / packets; 574 575 /* The following is a crude approximation of: 576 * wmem_default / (size + overhead) = desired_pkts_per_int 577 * rate / bits_per_byte / (size + ethernet overhead) = pkt_rate 578 * (desired_pkt_rate / pkt_rate) * usecs_per_sec = ITR value 579 * 580 * Assuming wmem_default is 212992 and overhead is 640 bytes per 581 * packet, (256 skb, 64 headroom, 320 shared info), we can reduce the 582 * formula down to 583 * 584 * (170 * (size + 24)) / (size + 640) = ITR 585 * 586 * We first do some math on the packet size and then finally bitshift 587 * by 8 after rounding up. We also have to account for PCIe link speed 588 * difference as ITR scales based on this. 589 */ 590 if (avg_wire_size <= 60) { 591 /* Start at 250k ints/sec */ 592 avg_wire_size = 4096; 593 } else if (avg_wire_size <= 380) { 594 /* 250K ints/sec to 60K ints/sec */ 595 avg_wire_size *= 40; 596 avg_wire_size += 1696; 597 } else if (avg_wire_size <= 1084) { 598 /* 60K ints/sec to 36K ints/sec */ 599 avg_wire_size *= 15; 600 avg_wire_size += 11452; 601 } else if (avg_wire_size <= 1980) { 602 /* 36K ints/sec to 30K ints/sec */ 603 avg_wire_size *= 5; 604 avg_wire_size += 22420; 605 } else { 606 /* plateau at a limit of 30K ints/sec */ 607 avg_wire_size = 32256; 608 } 609 610 /* If we are in low latency mode halve our delay which doubles the 611 * rate to somewhere between 100K to 16K ints/sec 612 */ 613 if (itr & IAVF_ITR_ADAPTIVE_LATENCY) 614 avg_wire_size /= 2; 615 616 /* Resultant value is 256 times larger than it needs to be. This 617 * gives us room to adjust the value as needed to either increase 618 * or decrease the value based on link speeds of 10G, 2.5G, 1G, etc. 619 * 620 * Use addition as we have already recorded the new latency flag 621 * for the ITR value. 622 */ 623 itr += DIV_ROUND_UP(avg_wire_size, 624 iavf_itr_divisor(q_vector->adapter)) * 625 IAVF_ITR_ADAPTIVE_MIN_INC; 626 627 if ((itr & IAVF_ITR_MASK) > IAVF_ITR_ADAPTIVE_MAX_USECS) { 628 itr &= IAVF_ITR_ADAPTIVE_LATENCY; 629 itr += IAVF_ITR_ADAPTIVE_MAX_USECS; 630 } 631 632 clear_counts: 633 /* write back value */ 634 rc->target_itr = itr; 635 636 /* next update should occur within next jiffy */ 637 rc->next_update = next_update + 1; 638 639 rc->total_bytes = 0; 640 rc->total_packets = 0; 641 } 642 643 /** 644 * iavf_setup_tx_descriptors - Allocate the Tx descriptors 645 * @tx_ring: the tx ring to set up 646 * 647 * Return 0 on success, negative on error 648 **/ 649 int iavf_setup_tx_descriptors(struct iavf_ring *tx_ring) 650 { 651 struct device *dev = tx_ring->dev; 652 int bi_size; 653 654 if (!dev) 655 return -ENOMEM; 656 657 /* warn if we are about to overwrite the pointer */ 658 WARN_ON(tx_ring->tx_bi); 659 bi_size = sizeof(struct iavf_tx_buffer) * tx_ring->count; 660 tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL); 661 if (!tx_ring->tx_bi) 662 goto err; 663 664 /* round up to nearest 4K */ 665 tx_ring->size = tx_ring->count * sizeof(struct iavf_tx_desc); 666 tx_ring->size = ALIGN(tx_ring->size, 4096); 667 tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size, 668 &tx_ring->dma, GFP_KERNEL); 669 if (!tx_ring->desc) { 670 dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n", 671 tx_ring->size); 672 goto err; 673 } 674 675 tx_ring->next_to_use = 0; 676 tx_ring->next_to_clean = 0; 677 tx_ring->tx_stats.prev_pkt_ctr = -1; 678 return 0; 679 680 err: 681 kfree(tx_ring->tx_bi); 682 tx_ring->tx_bi = NULL; 683 return -ENOMEM; 684 } 685 686 /** 687 * iavf_clean_rx_ring - Free Rx buffers 688 * @rx_ring: ring to be cleaned 689 **/ 690 static void iavf_clean_rx_ring(struct iavf_ring *rx_ring) 691 { 692 unsigned long bi_size; 693 u16 i; 694 695 /* ring already cleared, nothing to do */ 696 if (!rx_ring->rx_bi) 697 return; 698 699 if (rx_ring->skb) { 700 dev_kfree_skb(rx_ring->skb); 701 rx_ring->skb = NULL; 702 } 703 704 /* Free all the Rx ring sk_buffs */ 705 for (i = 0; i < rx_ring->count; i++) { 706 struct iavf_rx_buffer *rx_bi = &rx_ring->rx_bi[i]; 707 708 if (!rx_bi->page) 709 continue; 710 711 /* Invalidate cache lines that may have been written to by 712 * device so that we avoid corrupting memory. 713 */ 714 dma_sync_single_range_for_cpu(rx_ring->dev, 715 rx_bi->dma, 716 rx_bi->page_offset, 717 rx_ring->rx_buf_len, 718 DMA_FROM_DEVICE); 719 720 /* free resources associated with mapping */ 721 dma_unmap_page_attrs(rx_ring->dev, rx_bi->dma, 722 iavf_rx_pg_size(rx_ring), 723 DMA_FROM_DEVICE, 724 IAVF_RX_DMA_ATTR); 725 726 __page_frag_cache_drain(rx_bi->page, rx_bi->pagecnt_bias); 727 728 rx_bi->page = NULL; 729 rx_bi->page_offset = 0; 730 } 731 732 bi_size = sizeof(struct iavf_rx_buffer) * rx_ring->count; 733 memset(rx_ring->rx_bi, 0, bi_size); 734 735 /* Zero out the descriptor ring */ 736 memset(rx_ring->desc, 0, rx_ring->size); 737 738 rx_ring->next_to_alloc = 0; 739 rx_ring->next_to_clean = 0; 740 rx_ring->next_to_use = 0; 741 } 742 743 /** 744 * iavf_free_rx_resources - Free Rx resources 745 * @rx_ring: ring to clean the resources from 746 * 747 * Free all receive software resources 748 **/ 749 void iavf_free_rx_resources(struct iavf_ring *rx_ring) 750 { 751 iavf_clean_rx_ring(rx_ring); 752 kfree(rx_ring->rx_bi); 753 rx_ring->rx_bi = NULL; 754 755 if (rx_ring->desc) { 756 dma_free_coherent(rx_ring->dev, rx_ring->size, 757 rx_ring->desc, rx_ring->dma); 758 rx_ring->desc = NULL; 759 } 760 } 761 762 /** 763 * iavf_setup_rx_descriptors - Allocate Rx descriptors 764 * @rx_ring: Rx descriptor ring (for a specific queue) to setup 765 * 766 * Returns 0 on success, negative on failure 767 **/ 768 int iavf_setup_rx_descriptors(struct iavf_ring *rx_ring) 769 { 770 struct device *dev = rx_ring->dev; 771 int bi_size; 772 773 /* warn if we are about to overwrite the pointer */ 774 WARN_ON(rx_ring->rx_bi); 775 bi_size = sizeof(struct iavf_rx_buffer) * rx_ring->count; 776 rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL); 777 if (!rx_ring->rx_bi) 778 goto err; 779 780 u64_stats_init(&rx_ring->syncp); 781 782 /* Round up to nearest 4K */ 783 rx_ring->size = rx_ring->count * sizeof(union iavf_32byte_rx_desc); 784 rx_ring->size = ALIGN(rx_ring->size, 4096); 785 rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size, 786 &rx_ring->dma, GFP_KERNEL); 787 788 if (!rx_ring->desc) { 789 dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n", 790 rx_ring->size); 791 goto err; 792 } 793 794 rx_ring->next_to_alloc = 0; 795 rx_ring->next_to_clean = 0; 796 rx_ring->next_to_use = 0; 797 798 return 0; 799 err: 800 kfree(rx_ring->rx_bi); 801 rx_ring->rx_bi = NULL; 802 return -ENOMEM; 803 } 804 805 /** 806 * iavf_release_rx_desc - Store the new tail and head values 807 * @rx_ring: ring to bump 808 * @val: new head index 809 **/ 810 static void iavf_release_rx_desc(struct iavf_ring *rx_ring, u32 val) 811 { 812 rx_ring->next_to_use = val; 813 814 /* update next to alloc since we have filled the ring */ 815 rx_ring->next_to_alloc = val; 816 817 /* Force memory writes to complete before letting h/w 818 * know there are new descriptors to fetch. (Only 819 * applicable for weak-ordered memory model archs, 820 * such as IA-64). 821 */ 822 wmb(); 823 writel(val, rx_ring->tail); 824 } 825 826 /** 827 * iavf_rx_offset - Return expected offset into page to access data 828 * @rx_ring: Ring we are requesting offset of 829 * 830 * Returns the offset value for ring into the data buffer. 831 */ 832 static unsigned int iavf_rx_offset(struct iavf_ring *rx_ring) 833 { 834 return ring_uses_build_skb(rx_ring) ? IAVF_SKB_PAD : 0; 835 } 836 837 /** 838 * iavf_alloc_mapped_page - recycle or make a new page 839 * @rx_ring: ring to use 840 * @bi: rx_buffer struct to modify 841 * 842 * Returns true if the page was successfully allocated or 843 * reused. 844 **/ 845 static bool iavf_alloc_mapped_page(struct iavf_ring *rx_ring, 846 struct iavf_rx_buffer *bi) 847 { 848 struct page *page = bi->page; 849 dma_addr_t dma; 850 851 /* since we are recycling buffers we should seldom need to alloc */ 852 if (likely(page)) { 853 rx_ring->rx_stats.page_reuse_count++; 854 return true; 855 } 856 857 /* alloc new page for storage */ 858 page = dev_alloc_pages(iavf_rx_pg_order(rx_ring)); 859 if (unlikely(!page)) { 860 rx_ring->rx_stats.alloc_page_failed++; 861 return false; 862 } 863 864 /* map page for use */ 865 dma = dma_map_page_attrs(rx_ring->dev, page, 0, 866 iavf_rx_pg_size(rx_ring), 867 DMA_FROM_DEVICE, 868 IAVF_RX_DMA_ATTR); 869 870 /* if mapping failed free memory back to system since 871 * there isn't much point in holding memory we can't use 872 */ 873 if (dma_mapping_error(rx_ring->dev, dma)) { 874 __free_pages(page, iavf_rx_pg_order(rx_ring)); 875 rx_ring->rx_stats.alloc_page_failed++; 876 return false; 877 } 878 879 bi->dma = dma; 880 bi->page = page; 881 bi->page_offset = iavf_rx_offset(rx_ring); 882 883 /* initialize pagecnt_bias to 1 representing we fully own page */ 884 bi->pagecnt_bias = 1; 885 886 return true; 887 } 888 889 /** 890 * iavf_receive_skb - Send a completed packet up the stack 891 * @rx_ring: rx ring in play 892 * @skb: packet to send up 893 * @vlan_tag: vlan tag for packet 894 **/ 895 static void iavf_receive_skb(struct iavf_ring *rx_ring, 896 struct sk_buff *skb, u16 vlan_tag) 897 { 898 struct iavf_q_vector *q_vector = rx_ring->q_vector; 899 900 if ((rx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_RX) && 901 (vlan_tag & VLAN_VID_MASK)) 902 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag); 903 else if ((rx_ring->netdev->features & NETIF_F_HW_VLAN_STAG_RX) && 904 vlan_tag & VLAN_VID_MASK) 905 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021AD), vlan_tag); 906 907 napi_gro_receive(&q_vector->napi, skb); 908 } 909 910 /** 911 * iavf_alloc_rx_buffers - Replace used receive buffers 912 * @rx_ring: ring to place buffers on 913 * @cleaned_count: number of buffers to replace 914 * 915 * Returns false if all allocations were successful, true if any fail 916 **/ 917 bool iavf_alloc_rx_buffers(struct iavf_ring *rx_ring, u16 cleaned_count) 918 { 919 u16 ntu = rx_ring->next_to_use; 920 union iavf_rx_desc *rx_desc; 921 struct iavf_rx_buffer *bi; 922 923 /* do nothing if no valid netdev defined */ 924 if (!rx_ring->netdev || !cleaned_count) 925 return false; 926 927 rx_desc = IAVF_RX_DESC(rx_ring, ntu); 928 bi = &rx_ring->rx_bi[ntu]; 929 930 do { 931 if (!iavf_alloc_mapped_page(rx_ring, bi)) 932 goto no_buffers; 933 934 /* sync the buffer for use by the device */ 935 dma_sync_single_range_for_device(rx_ring->dev, bi->dma, 936 bi->page_offset, 937 rx_ring->rx_buf_len, 938 DMA_FROM_DEVICE); 939 940 /* Refresh the desc even if buffer_addrs didn't change 941 * because each write-back erases this info. 942 */ 943 rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset); 944 945 rx_desc++; 946 bi++; 947 ntu++; 948 if (unlikely(ntu == rx_ring->count)) { 949 rx_desc = IAVF_RX_DESC(rx_ring, 0); 950 bi = rx_ring->rx_bi; 951 ntu = 0; 952 } 953 954 /* clear the status bits for the next_to_use descriptor */ 955 rx_desc->wb.qword1.status_error_len = 0; 956 957 cleaned_count--; 958 } while (cleaned_count); 959 960 if (rx_ring->next_to_use != ntu) 961 iavf_release_rx_desc(rx_ring, ntu); 962 963 return false; 964 965 no_buffers: 966 if (rx_ring->next_to_use != ntu) 967 iavf_release_rx_desc(rx_ring, ntu); 968 969 /* make sure to come back via polling to try again after 970 * allocation failure 971 */ 972 return true; 973 } 974 975 /** 976 * iavf_rx_checksum - Indicate in skb if hw indicated a good cksum 977 * @vsi: the VSI we care about 978 * @skb: skb currently being received and modified 979 * @rx_desc: the receive descriptor 980 **/ 981 static void iavf_rx_checksum(struct iavf_vsi *vsi, 982 struct sk_buff *skb, 983 union iavf_rx_desc *rx_desc) 984 { 985 struct iavf_rx_ptype_decoded decoded; 986 u32 rx_error, rx_status; 987 bool ipv4, ipv6; 988 u8 ptype; 989 u64 qword; 990 991 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len); 992 ptype = FIELD_GET(IAVF_RXD_QW1_PTYPE_MASK, qword); 993 rx_error = FIELD_GET(IAVF_RXD_QW1_ERROR_MASK, qword); 994 rx_status = FIELD_GET(IAVF_RXD_QW1_STATUS_MASK, qword); 995 decoded = decode_rx_desc_ptype(ptype); 996 997 skb->ip_summed = CHECKSUM_NONE; 998 999 skb_checksum_none_assert(skb); 1000 1001 /* Rx csum enabled and ip headers found? */ 1002 if (!(vsi->netdev->features & NETIF_F_RXCSUM)) 1003 return; 1004 1005 /* did the hardware decode the packet and checksum? */ 1006 if (!(rx_status & BIT(IAVF_RX_DESC_STATUS_L3L4P_SHIFT))) 1007 return; 1008 1009 /* both known and outer_ip must be set for the below code to work */ 1010 if (!(decoded.known && decoded.outer_ip)) 1011 return; 1012 1013 ipv4 = (decoded.outer_ip == IAVF_RX_PTYPE_OUTER_IP) && 1014 (decoded.outer_ip_ver == IAVF_RX_PTYPE_OUTER_IPV4); 1015 ipv6 = (decoded.outer_ip == IAVF_RX_PTYPE_OUTER_IP) && 1016 (decoded.outer_ip_ver == IAVF_RX_PTYPE_OUTER_IPV6); 1017 1018 if (ipv4 && 1019 (rx_error & (BIT(IAVF_RX_DESC_ERROR_IPE_SHIFT) | 1020 BIT(IAVF_RX_DESC_ERROR_EIPE_SHIFT)))) 1021 goto checksum_fail; 1022 1023 /* likely incorrect csum if alternate IP extension headers found */ 1024 if (ipv6 && 1025 rx_status & BIT(IAVF_RX_DESC_STATUS_IPV6EXADD_SHIFT)) 1026 /* don't increment checksum err here, non-fatal err */ 1027 return; 1028 1029 /* there was some L4 error, count error and punt packet to the stack */ 1030 if (rx_error & BIT(IAVF_RX_DESC_ERROR_L4E_SHIFT)) 1031 goto checksum_fail; 1032 1033 /* handle packets that were not able to be checksummed due 1034 * to arrival speed, in this case the stack can compute 1035 * the csum. 1036 */ 1037 if (rx_error & BIT(IAVF_RX_DESC_ERROR_PPRS_SHIFT)) 1038 return; 1039 1040 /* Only report checksum unnecessary for TCP, UDP, or SCTP */ 1041 switch (decoded.inner_prot) { 1042 case IAVF_RX_PTYPE_INNER_PROT_TCP: 1043 case IAVF_RX_PTYPE_INNER_PROT_UDP: 1044 case IAVF_RX_PTYPE_INNER_PROT_SCTP: 1045 skb->ip_summed = CHECKSUM_UNNECESSARY; 1046 fallthrough; 1047 default: 1048 break; 1049 } 1050 1051 return; 1052 1053 checksum_fail: 1054 vsi->back->hw_csum_rx_error++; 1055 } 1056 1057 /** 1058 * iavf_ptype_to_htype - get a hash type 1059 * @ptype: the ptype value from the descriptor 1060 * 1061 * Returns a hash type to be used by skb_set_hash 1062 **/ 1063 static int iavf_ptype_to_htype(u8 ptype) 1064 { 1065 struct iavf_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype); 1066 1067 if (!decoded.known) 1068 return PKT_HASH_TYPE_NONE; 1069 1070 if (decoded.outer_ip == IAVF_RX_PTYPE_OUTER_IP && 1071 decoded.payload_layer == IAVF_RX_PTYPE_PAYLOAD_LAYER_PAY4) 1072 return PKT_HASH_TYPE_L4; 1073 else if (decoded.outer_ip == IAVF_RX_PTYPE_OUTER_IP && 1074 decoded.payload_layer == IAVF_RX_PTYPE_PAYLOAD_LAYER_PAY3) 1075 return PKT_HASH_TYPE_L3; 1076 else 1077 return PKT_HASH_TYPE_L2; 1078 } 1079 1080 /** 1081 * iavf_rx_hash - set the hash value in the skb 1082 * @ring: descriptor ring 1083 * @rx_desc: specific descriptor 1084 * @skb: skb currently being received and modified 1085 * @rx_ptype: Rx packet type 1086 **/ 1087 static void iavf_rx_hash(struct iavf_ring *ring, 1088 union iavf_rx_desc *rx_desc, 1089 struct sk_buff *skb, 1090 u8 rx_ptype) 1091 { 1092 u32 hash; 1093 const __le64 rss_mask = 1094 cpu_to_le64((u64)IAVF_RX_DESC_FLTSTAT_RSS_HASH << 1095 IAVF_RX_DESC_STATUS_FLTSTAT_SHIFT); 1096 1097 if (!(ring->netdev->features & NETIF_F_RXHASH)) 1098 return; 1099 1100 if ((rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask) { 1101 hash = le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss); 1102 skb_set_hash(skb, hash, iavf_ptype_to_htype(rx_ptype)); 1103 } 1104 } 1105 1106 /** 1107 * iavf_process_skb_fields - Populate skb header fields from Rx descriptor 1108 * @rx_ring: rx descriptor ring packet is being transacted on 1109 * @rx_desc: pointer to the EOP Rx descriptor 1110 * @skb: pointer to current skb being populated 1111 * @rx_ptype: the packet type decoded by hardware 1112 * 1113 * This function checks the ring, descriptor, and packet information in 1114 * order to populate the hash, checksum, VLAN, protocol, and 1115 * other fields within the skb. 1116 **/ 1117 static void 1118 iavf_process_skb_fields(struct iavf_ring *rx_ring, 1119 union iavf_rx_desc *rx_desc, struct sk_buff *skb, 1120 u8 rx_ptype) 1121 { 1122 iavf_rx_hash(rx_ring, rx_desc, skb, rx_ptype); 1123 1124 iavf_rx_checksum(rx_ring->vsi, skb, rx_desc); 1125 1126 skb_record_rx_queue(skb, rx_ring->queue_index); 1127 1128 /* modifies the skb - consumes the enet header */ 1129 skb->protocol = eth_type_trans(skb, rx_ring->netdev); 1130 } 1131 1132 /** 1133 * iavf_cleanup_headers - Correct empty headers 1134 * @rx_ring: rx descriptor ring packet is being transacted on 1135 * @skb: pointer to current skb being fixed 1136 * 1137 * Also address the case where we are pulling data in on pages only 1138 * and as such no data is present in the skb header. 1139 * 1140 * In addition if skb is not at least 60 bytes we need to pad it so that 1141 * it is large enough to qualify as a valid Ethernet frame. 1142 * 1143 * Returns true if an error was encountered and skb was freed. 1144 **/ 1145 static bool iavf_cleanup_headers(struct iavf_ring *rx_ring, struct sk_buff *skb) 1146 { 1147 /* if eth_skb_pad returns an error the skb was freed */ 1148 if (eth_skb_pad(skb)) 1149 return true; 1150 1151 return false; 1152 } 1153 1154 /** 1155 * iavf_reuse_rx_page - page flip buffer and store it back on the ring 1156 * @rx_ring: rx descriptor ring to store buffers on 1157 * @old_buff: donor buffer to have page reused 1158 * 1159 * Synchronizes page for reuse by the adapter 1160 **/ 1161 static void iavf_reuse_rx_page(struct iavf_ring *rx_ring, 1162 struct iavf_rx_buffer *old_buff) 1163 { 1164 struct iavf_rx_buffer *new_buff; 1165 u16 nta = rx_ring->next_to_alloc; 1166 1167 new_buff = &rx_ring->rx_bi[nta]; 1168 1169 /* update, and store next to alloc */ 1170 nta++; 1171 rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0; 1172 1173 /* transfer page from old buffer to new buffer */ 1174 new_buff->dma = old_buff->dma; 1175 new_buff->page = old_buff->page; 1176 new_buff->page_offset = old_buff->page_offset; 1177 new_buff->pagecnt_bias = old_buff->pagecnt_bias; 1178 } 1179 1180 /** 1181 * iavf_can_reuse_rx_page - Determine if this page can be reused by 1182 * the adapter for another receive 1183 * 1184 * @rx_buffer: buffer containing the page 1185 * 1186 * If page is reusable, rx_buffer->page_offset is adjusted to point to 1187 * an unused region in the page. 1188 * 1189 * For small pages, @truesize will be a constant value, half the size 1190 * of the memory at page. We'll attempt to alternate between high and 1191 * low halves of the page, with one half ready for use by the hardware 1192 * and the other half being consumed by the stack. We use the page 1193 * ref count to determine whether the stack has finished consuming the 1194 * portion of this page that was passed up with a previous packet. If 1195 * the page ref count is >1, we'll assume the "other" half page is 1196 * still busy, and this page cannot be reused. 1197 * 1198 * For larger pages, @truesize will be the actual space used by the 1199 * received packet (adjusted upward to an even multiple of the cache 1200 * line size). This will advance through the page by the amount 1201 * actually consumed by the received packets while there is still 1202 * space for a buffer. Each region of larger pages will be used at 1203 * most once, after which the page will not be reused. 1204 * 1205 * In either case, if the page is reusable its refcount is increased. 1206 **/ 1207 static bool iavf_can_reuse_rx_page(struct iavf_rx_buffer *rx_buffer) 1208 { 1209 unsigned int pagecnt_bias = rx_buffer->pagecnt_bias; 1210 struct page *page = rx_buffer->page; 1211 1212 /* Is any reuse possible? */ 1213 if (!dev_page_is_reusable(page)) 1214 return false; 1215 1216 #if (PAGE_SIZE < 8192) 1217 /* if we are only owner of page we can reuse it */ 1218 if (unlikely((page_count(page) - pagecnt_bias) > 1)) 1219 return false; 1220 #else 1221 #define IAVF_LAST_OFFSET \ 1222 (SKB_WITH_OVERHEAD(PAGE_SIZE) - IAVF_RXBUFFER_2048) 1223 if (rx_buffer->page_offset > IAVF_LAST_OFFSET) 1224 return false; 1225 #endif 1226 1227 /* If we have drained the page fragment pool we need to update 1228 * the pagecnt_bias and page count so that we fully restock the 1229 * number of references the driver holds. 1230 */ 1231 if (unlikely(!pagecnt_bias)) { 1232 page_ref_add(page, USHRT_MAX); 1233 rx_buffer->pagecnt_bias = USHRT_MAX; 1234 } 1235 1236 return true; 1237 } 1238 1239 /** 1240 * iavf_add_rx_frag - Add contents of Rx buffer to sk_buff 1241 * @rx_ring: rx descriptor ring to transact packets on 1242 * @rx_buffer: buffer containing page to add 1243 * @skb: sk_buff to place the data into 1244 * @size: packet length from rx_desc 1245 * 1246 * This function will add the data contained in rx_buffer->page to the skb. 1247 * It will just attach the page as a frag to the skb. 1248 * 1249 * The function will then update the page offset. 1250 **/ 1251 static void iavf_add_rx_frag(struct iavf_ring *rx_ring, 1252 struct iavf_rx_buffer *rx_buffer, 1253 struct sk_buff *skb, 1254 unsigned int size) 1255 { 1256 #if (PAGE_SIZE < 8192) 1257 unsigned int truesize = iavf_rx_pg_size(rx_ring) / 2; 1258 #else 1259 unsigned int truesize = SKB_DATA_ALIGN(size + iavf_rx_offset(rx_ring)); 1260 #endif 1261 1262 if (!size) 1263 return; 1264 1265 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page, 1266 rx_buffer->page_offset, size, truesize); 1267 1268 /* page is being used so we must update the page offset */ 1269 #if (PAGE_SIZE < 8192) 1270 rx_buffer->page_offset ^= truesize; 1271 #else 1272 rx_buffer->page_offset += truesize; 1273 #endif 1274 } 1275 1276 /** 1277 * iavf_get_rx_buffer - Fetch Rx buffer and synchronize data for use 1278 * @rx_ring: rx descriptor ring to transact packets on 1279 * @size: size of buffer to add to skb 1280 * 1281 * This function will pull an Rx buffer from the ring and synchronize it 1282 * for use by the CPU. 1283 */ 1284 static struct iavf_rx_buffer *iavf_get_rx_buffer(struct iavf_ring *rx_ring, 1285 const unsigned int size) 1286 { 1287 struct iavf_rx_buffer *rx_buffer; 1288 1289 rx_buffer = &rx_ring->rx_bi[rx_ring->next_to_clean]; 1290 prefetchw(rx_buffer->page); 1291 if (!size) 1292 return rx_buffer; 1293 1294 /* we are reusing so sync this buffer for CPU use */ 1295 dma_sync_single_range_for_cpu(rx_ring->dev, 1296 rx_buffer->dma, 1297 rx_buffer->page_offset, 1298 size, 1299 DMA_FROM_DEVICE); 1300 1301 /* We have pulled a buffer for use, so decrement pagecnt_bias */ 1302 rx_buffer->pagecnt_bias--; 1303 1304 return rx_buffer; 1305 } 1306 1307 /** 1308 * iavf_construct_skb - Allocate skb and populate it 1309 * @rx_ring: rx descriptor ring to transact packets on 1310 * @rx_buffer: rx buffer to pull data from 1311 * @size: size of buffer to add to skb 1312 * 1313 * This function allocates an skb. It then populates it with the page 1314 * data from the current receive descriptor, taking care to set up the 1315 * skb correctly. 1316 */ 1317 static struct sk_buff *iavf_construct_skb(struct iavf_ring *rx_ring, 1318 struct iavf_rx_buffer *rx_buffer, 1319 unsigned int size) 1320 { 1321 void *va; 1322 #if (PAGE_SIZE < 8192) 1323 unsigned int truesize = iavf_rx_pg_size(rx_ring) / 2; 1324 #else 1325 unsigned int truesize = SKB_DATA_ALIGN(size); 1326 #endif 1327 unsigned int headlen; 1328 struct sk_buff *skb; 1329 1330 if (!rx_buffer) 1331 return NULL; 1332 /* prefetch first cache line of first page */ 1333 va = page_address(rx_buffer->page) + rx_buffer->page_offset; 1334 net_prefetch(va); 1335 1336 /* allocate a skb to store the frags */ 1337 skb = __napi_alloc_skb(&rx_ring->q_vector->napi, 1338 IAVF_RX_HDR_SIZE, 1339 GFP_ATOMIC | __GFP_NOWARN); 1340 if (unlikely(!skb)) 1341 return NULL; 1342 1343 /* Determine available headroom for copy */ 1344 headlen = size; 1345 if (headlen > IAVF_RX_HDR_SIZE) 1346 headlen = eth_get_headlen(skb->dev, va, IAVF_RX_HDR_SIZE); 1347 1348 /* align pull length to size of long to optimize memcpy performance */ 1349 memcpy(__skb_put(skb, headlen), va, ALIGN(headlen, sizeof(long))); 1350 1351 /* update all of the pointers */ 1352 size -= headlen; 1353 if (size) { 1354 skb_add_rx_frag(skb, 0, rx_buffer->page, 1355 rx_buffer->page_offset + headlen, 1356 size, truesize); 1357 1358 /* buffer is used by skb, update page_offset */ 1359 #if (PAGE_SIZE < 8192) 1360 rx_buffer->page_offset ^= truesize; 1361 #else 1362 rx_buffer->page_offset += truesize; 1363 #endif 1364 } else { 1365 /* buffer is unused, reset bias back to rx_buffer */ 1366 rx_buffer->pagecnt_bias++; 1367 } 1368 1369 return skb; 1370 } 1371 1372 /** 1373 * iavf_build_skb - Build skb around an existing buffer 1374 * @rx_ring: Rx descriptor ring to transact packets on 1375 * @rx_buffer: Rx buffer to pull data from 1376 * @size: size of buffer to add to skb 1377 * 1378 * This function builds an skb around an existing Rx buffer, taking care 1379 * to set up the skb correctly and avoid any memcpy overhead. 1380 */ 1381 static struct sk_buff *iavf_build_skb(struct iavf_ring *rx_ring, 1382 struct iavf_rx_buffer *rx_buffer, 1383 unsigned int size) 1384 { 1385 void *va; 1386 #if (PAGE_SIZE < 8192) 1387 unsigned int truesize = iavf_rx_pg_size(rx_ring) / 2; 1388 #else 1389 unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) + 1390 SKB_DATA_ALIGN(IAVF_SKB_PAD + size); 1391 #endif 1392 struct sk_buff *skb; 1393 1394 if (!rx_buffer || !size) 1395 return NULL; 1396 /* prefetch first cache line of first page */ 1397 va = page_address(rx_buffer->page) + rx_buffer->page_offset; 1398 net_prefetch(va); 1399 1400 /* build an skb around the page buffer */ 1401 skb = napi_build_skb(va - IAVF_SKB_PAD, truesize); 1402 if (unlikely(!skb)) 1403 return NULL; 1404 1405 /* update pointers within the skb to store the data */ 1406 skb_reserve(skb, IAVF_SKB_PAD); 1407 __skb_put(skb, size); 1408 1409 /* buffer is used by skb, update page_offset */ 1410 #if (PAGE_SIZE < 8192) 1411 rx_buffer->page_offset ^= truesize; 1412 #else 1413 rx_buffer->page_offset += truesize; 1414 #endif 1415 1416 return skb; 1417 } 1418 1419 /** 1420 * iavf_put_rx_buffer - Clean up used buffer and either recycle or free 1421 * @rx_ring: rx descriptor ring to transact packets on 1422 * @rx_buffer: rx buffer to pull data from 1423 * 1424 * This function will clean up the contents of the rx_buffer. It will 1425 * either recycle the buffer or unmap it and free the associated resources. 1426 */ 1427 static void iavf_put_rx_buffer(struct iavf_ring *rx_ring, 1428 struct iavf_rx_buffer *rx_buffer) 1429 { 1430 if (!rx_buffer) 1431 return; 1432 1433 if (iavf_can_reuse_rx_page(rx_buffer)) { 1434 /* hand second half of page back to the ring */ 1435 iavf_reuse_rx_page(rx_ring, rx_buffer); 1436 rx_ring->rx_stats.page_reuse_count++; 1437 } else { 1438 /* we are not reusing the buffer so unmap it */ 1439 dma_unmap_page_attrs(rx_ring->dev, rx_buffer->dma, 1440 iavf_rx_pg_size(rx_ring), 1441 DMA_FROM_DEVICE, IAVF_RX_DMA_ATTR); 1442 __page_frag_cache_drain(rx_buffer->page, 1443 rx_buffer->pagecnt_bias); 1444 } 1445 1446 /* clear contents of buffer_info */ 1447 rx_buffer->page = NULL; 1448 } 1449 1450 /** 1451 * iavf_is_non_eop - process handling of non-EOP buffers 1452 * @rx_ring: Rx ring being processed 1453 * @rx_desc: Rx descriptor for current buffer 1454 * @skb: Current socket buffer containing buffer in progress 1455 * 1456 * This function updates next to clean. If the buffer is an EOP buffer 1457 * this function exits returning false, otherwise it will place the 1458 * sk_buff in the next buffer to be chained and return true indicating 1459 * that this is in fact a non-EOP buffer. 1460 **/ 1461 static bool iavf_is_non_eop(struct iavf_ring *rx_ring, 1462 union iavf_rx_desc *rx_desc, 1463 struct sk_buff *skb) 1464 { 1465 u32 ntc = rx_ring->next_to_clean + 1; 1466 1467 /* fetch, update, and store next to clean */ 1468 ntc = (ntc < rx_ring->count) ? ntc : 0; 1469 rx_ring->next_to_clean = ntc; 1470 1471 prefetch(IAVF_RX_DESC(rx_ring, ntc)); 1472 1473 /* if we are the last buffer then there is nothing else to do */ 1474 #define IAVF_RXD_EOF BIT(IAVF_RX_DESC_STATUS_EOF_SHIFT) 1475 if (likely(iavf_test_staterr(rx_desc, IAVF_RXD_EOF))) 1476 return false; 1477 1478 rx_ring->rx_stats.non_eop_descs++; 1479 1480 return true; 1481 } 1482 1483 /** 1484 * iavf_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf 1485 * @rx_ring: rx descriptor ring to transact packets on 1486 * @budget: Total limit on number of packets to process 1487 * 1488 * This function provides a "bounce buffer" approach to Rx interrupt 1489 * processing. The advantage to this is that on systems that have 1490 * expensive overhead for IOMMU access this provides a means of avoiding 1491 * it by maintaining the mapping of the page to the system. 1492 * 1493 * Returns amount of work completed 1494 **/ 1495 static int iavf_clean_rx_irq(struct iavf_ring *rx_ring, int budget) 1496 { 1497 unsigned int total_rx_bytes = 0, total_rx_packets = 0; 1498 struct sk_buff *skb = rx_ring->skb; 1499 u16 cleaned_count = IAVF_DESC_UNUSED(rx_ring); 1500 bool failure = false; 1501 1502 while (likely(total_rx_packets < (unsigned int)budget)) { 1503 struct iavf_rx_buffer *rx_buffer; 1504 union iavf_rx_desc *rx_desc; 1505 unsigned int size; 1506 u16 vlan_tag = 0; 1507 u8 rx_ptype; 1508 u64 qword; 1509 1510 /* return some buffers to hardware, one at a time is too slow */ 1511 if (cleaned_count >= IAVF_RX_BUFFER_WRITE) { 1512 failure = failure || 1513 iavf_alloc_rx_buffers(rx_ring, cleaned_count); 1514 cleaned_count = 0; 1515 } 1516 1517 rx_desc = IAVF_RX_DESC(rx_ring, rx_ring->next_to_clean); 1518 1519 /* status_error_len will always be zero for unused descriptors 1520 * because it's cleared in cleanup, and overlaps with hdr_addr 1521 * which is always zero because packet split isn't used, if the 1522 * hardware wrote DD then the length will be non-zero 1523 */ 1524 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len); 1525 1526 /* This memory barrier is needed to keep us from reading 1527 * any other fields out of the rx_desc until we have 1528 * verified the descriptor has been written back. 1529 */ 1530 dma_rmb(); 1531 #define IAVF_RXD_DD BIT(IAVF_RX_DESC_STATUS_DD_SHIFT) 1532 if (!iavf_test_staterr(rx_desc, IAVF_RXD_DD)) 1533 break; 1534 1535 size = FIELD_GET(IAVF_RXD_QW1_LENGTH_PBUF_MASK, qword); 1536 1537 iavf_trace(clean_rx_irq, rx_ring, rx_desc, skb); 1538 rx_buffer = iavf_get_rx_buffer(rx_ring, size); 1539 1540 /* retrieve a buffer from the ring */ 1541 if (skb) 1542 iavf_add_rx_frag(rx_ring, rx_buffer, skb, size); 1543 else if (ring_uses_build_skb(rx_ring)) 1544 skb = iavf_build_skb(rx_ring, rx_buffer, size); 1545 else 1546 skb = iavf_construct_skb(rx_ring, rx_buffer, size); 1547 1548 /* exit if we failed to retrieve a buffer */ 1549 if (!skb) { 1550 rx_ring->rx_stats.alloc_buff_failed++; 1551 if (rx_buffer && size) 1552 rx_buffer->pagecnt_bias++; 1553 break; 1554 } 1555 1556 iavf_put_rx_buffer(rx_ring, rx_buffer); 1557 cleaned_count++; 1558 1559 if (iavf_is_non_eop(rx_ring, rx_desc, skb)) 1560 continue; 1561 1562 /* ERR_MASK will only have valid bits if EOP set, and 1563 * what we are doing here is actually checking 1564 * IAVF_RX_DESC_ERROR_RXE_SHIFT, since it is the zeroth bit in 1565 * the error field 1566 */ 1567 if (unlikely(iavf_test_staterr(rx_desc, BIT(IAVF_RXD_QW1_ERROR_SHIFT)))) { 1568 dev_kfree_skb_any(skb); 1569 skb = NULL; 1570 continue; 1571 } 1572 1573 if (iavf_cleanup_headers(rx_ring, skb)) { 1574 skb = NULL; 1575 continue; 1576 } 1577 1578 /* probably a little skewed due to removing CRC */ 1579 total_rx_bytes += skb->len; 1580 1581 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len); 1582 rx_ptype = FIELD_GET(IAVF_RXD_QW1_PTYPE_MASK, qword); 1583 1584 /* populate checksum, VLAN, and protocol */ 1585 iavf_process_skb_fields(rx_ring, rx_desc, skb, rx_ptype); 1586 1587 if (qword & BIT(IAVF_RX_DESC_STATUS_L2TAG1P_SHIFT) && 1588 rx_ring->flags & IAVF_TXRX_FLAGS_VLAN_TAG_LOC_L2TAG1) 1589 vlan_tag = le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1); 1590 if (rx_desc->wb.qword2.ext_status & 1591 cpu_to_le16(BIT(IAVF_RX_DESC_EXT_STATUS_L2TAG2P_SHIFT)) && 1592 rx_ring->flags & IAVF_RXR_FLAGS_VLAN_TAG_LOC_L2TAG2_2) 1593 vlan_tag = le16_to_cpu(rx_desc->wb.qword2.l2tag2_2); 1594 1595 iavf_trace(clean_rx_irq_rx, rx_ring, rx_desc, skb); 1596 iavf_receive_skb(rx_ring, skb, vlan_tag); 1597 skb = NULL; 1598 1599 /* update budget accounting */ 1600 total_rx_packets++; 1601 } 1602 1603 rx_ring->skb = skb; 1604 1605 u64_stats_update_begin(&rx_ring->syncp); 1606 rx_ring->stats.packets += total_rx_packets; 1607 rx_ring->stats.bytes += total_rx_bytes; 1608 u64_stats_update_end(&rx_ring->syncp); 1609 rx_ring->q_vector->rx.total_packets += total_rx_packets; 1610 rx_ring->q_vector->rx.total_bytes += total_rx_bytes; 1611 1612 /* guarantee a trip back through this routine if there was a failure */ 1613 return failure ? budget : (int)total_rx_packets; 1614 } 1615 1616 static inline u32 iavf_buildreg_itr(const int type, u16 itr) 1617 { 1618 u32 val; 1619 1620 /* We don't bother with setting the CLEARPBA bit as the data sheet 1621 * points out doing so is "meaningless since it was already 1622 * auto-cleared". The auto-clearing happens when the interrupt is 1623 * asserted. 1624 * 1625 * Hardware errata 28 for also indicates that writing to a 1626 * xxINT_DYN_CTLx CSR with INTENA_MSK (bit 31) set to 0 will clear 1627 * an event in the PBA anyway so we need to rely on the automask 1628 * to hold pending events for us until the interrupt is re-enabled 1629 * 1630 * The itr value is reported in microseconds, and the register 1631 * value is recorded in 2 microsecond units. For this reason we 1632 * only need to shift by the interval shift - 1 instead of the 1633 * full value. 1634 */ 1635 itr &= IAVF_ITR_MASK; 1636 1637 val = IAVF_VFINT_DYN_CTLN1_INTENA_MASK | 1638 (type << IAVF_VFINT_DYN_CTLN1_ITR_INDX_SHIFT) | 1639 (itr << (IAVF_VFINT_DYN_CTLN1_INTERVAL_SHIFT - 1)); 1640 1641 return val; 1642 } 1643 1644 /* a small macro to shorten up some long lines */ 1645 #define INTREG IAVF_VFINT_DYN_CTLN1 1646 1647 /* The act of updating the ITR will cause it to immediately trigger. In order 1648 * to prevent this from throwing off adaptive update statistics we defer the 1649 * update so that it can only happen so often. So after either Tx or Rx are 1650 * updated we make the adaptive scheme wait until either the ITR completely 1651 * expires via the next_update expiration or we have been through at least 1652 * 3 interrupts. 1653 */ 1654 #define ITR_COUNTDOWN_START 3 1655 1656 /** 1657 * iavf_update_enable_itr - Update itr and re-enable MSIX interrupt 1658 * @vsi: the VSI we care about 1659 * @q_vector: q_vector for which itr is being updated and interrupt enabled 1660 * 1661 **/ 1662 static void iavf_update_enable_itr(struct iavf_vsi *vsi, 1663 struct iavf_q_vector *q_vector) 1664 { 1665 struct iavf_hw *hw = &vsi->back->hw; 1666 u32 intval; 1667 1668 /* These will do nothing if dynamic updates are not enabled */ 1669 iavf_update_itr(q_vector, &q_vector->tx); 1670 iavf_update_itr(q_vector, &q_vector->rx); 1671 1672 /* This block of logic allows us to get away with only updating 1673 * one ITR value with each interrupt. The idea is to perform a 1674 * pseudo-lazy update with the following criteria. 1675 * 1676 * 1. Rx is given higher priority than Tx if both are in same state 1677 * 2. If we must reduce an ITR that is given highest priority. 1678 * 3. We then give priority to increasing ITR based on amount. 1679 */ 1680 if (q_vector->rx.target_itr < q_vector->rx.current_itr) { 1681 /* Rx ITR needs to be reduced, this is highest priority */ 1682 intval = iavf_buildreg_itr(IAVF_RX_ITR, 1683 q_vector->rx.target_itr); 1684 q_vector->rx.current_itr = q_vector->rx.target_itr; 1685 q_vector->itr_countdown = ITR_COUNTDOWN_START; 1686 } else if ((q_vector->tx.target_itr < q_vector->tx.current_itr) || 1687 ((q_vector->rx.target_itr - q_vector->rx.current_itr) < 1688 (q_vector->tx.target_itr - q_vector->tx.current_itr))) { 1689 /* Tx ITR needs to be reduced, this is second priority 1690 * Tx ITR needs to be increased more than Rx, fourth priority 1691 */ 1692 intval = iavf_buildreg_itr(IAVF_TX_ITR, 1693 q_vector->tx.target_itr); 1694 q_vector->tx.current_itr = q_vector->tx.target_itr; 1695 q_vector->itr_countdown = ITR_COUNTDOWN_START; 1696 } else if (q_vector->rx.current_itr != q_vector->rx.target_itr) { 1697 /* Rx ITR needs to be increased, third priority */ 1698 intval = iavf_buildreg_itr(IAVF_RX_ITR, 1699 q_vector->rx.target_itr); 1700 q_vector->rx.current_itr = q_vector->rx.target_itr; 1701 q_vector->itr_countdown = ITR_COUNTDOWN_START; 1702 } else { 1703 /* No ITR update, lowest priority */ 1704 intval = iavf_buildreg_itr(IAVF_ITR_NONE, 0); 1705 if (q_vector->itr_countdown) 1706 q_vector->itr_countdown--; 1707 } 1708 1709 if (!test_bit(__IAVF_VSI_DOWN, vsi->state)) 1710 wr32(hw, INTREG(q_vector->reg_idx), intval); 1711 } 1712 1713 /** 1714 * iavf_napi_poll - NAPI polling Rx/Tx cleanup routine 1715 * @napi: napi struct with our devices info in it 1716 * @budget: amount of work driver is allowed to do this pass, in packets 1717 * 1718 * This function will clean all queues associated with a q_vector. 1719 * 1720 * Returns the amount of work done 1721 **/ 1722 int iavf_napi_poll(struct napi_struct *napi, int budget) 1723 { 1724 struct iavf_q_vector *q_vector = 1725 container_of(napi, struct iavf_q_vector, napi); 1726 struct iavf_vsi *vsi = q_vector->vsi; 1727 struct iavf_ring *ring; 1728 bool clean_complete = true; 1729 bool arm_wb = false; 1730 int budget_per_ring; 1731 int work_done = 0; 1732 1733 if (test_bit(__IAVF_VSI_DOWN, vsi->state)) { 1734 napi_complete(napi); 1735 return 0; 1736 } 1737 1738 /* Since the actual Tx work is minimal, we can give the Tx a larger 1739 * budget and be more aggressive about cleaning up the Tx descriptors. 1740 */ 1741 iavf_for_each_ring(ring, q_vector->tx) { 1742 if (!iavf_clean_tx_irq(vsi, ring, budget)) { 1743 clean_complete = false; 1744 continue; 1745 } 1746 arm_wb |= ring->arm_wb; 1747 ring->arm_wb = false; 1748 } 1749 1750 /* Handle case where we are called by netpoll with a budget of 0 */ 1751 if (budget <= 0) 1752 goto tx_only; 1753 1754 /* We attempt to distribute budget to each Rx queue fairly, but don't 1755 * allow the budget to go below 1 because that would exit polling early. 1756 */ 1757 budget_per_ring = max(budget/q_vector->num_ringpairs, 1); 1758 1759 iavf_for_each_ring(ring, q_vector->rx) { 1760 int cleaned = iavf_clean_rx_irq(ring, budget_per_ring); 1761 1762 work_done += cleaned; 1763 /* if we clean as many as budgeted, we must not be done */ 1764 if (cleaned >= budget_per_ring) 1765 clean_complete = false; 1766 } 1767 1768 /* If work not completed, return budget and polling will return */ 1769 if (!clean_complete) { 1770 int cpu_id = smp_processor_id(); 1771 1772 /* It is possible that the interrupt affinity has changed but, 1773 * if the cpu is pegged at 100%, polling will never exit while 1774 * traffic continues and the interrupt will be stuck on this 1775 * cpu. We check to make sure affinity is correct before we 1776 * continue to poll, otherwise we must stop polling so the 1777 * interrupt can move to the correct cpu. 1778 */ 1779 if (!cpumask_test_cpu(cpu_id, &q_vector->affinity_mask)) { 1780 /* Tell napi that we are done polling */ 1781 napi_complete_done(napi, work_done); 1782 1783 /* Force an interrupt */ 1784 iavf_force_wb(vsi, q_vector); 1785 1786 /* Return budget-1 so that polling stops */ 1787 return budget - 1; 1788 } 1789 tx_only: 1790 if (arm_wb) { 1791 q_vector->tx.ring[0].tx_stats.tx_force_wb++; 1792 iavf_enable_wb_on_itr(vsi, q_vector); 1793 } 1794 return budget; 1795 } 1796 1797 if (vsi->back->flags & IAVF_TXR_FLAGS_WB_ON_ITR) 1798 q_vector->arm_wb_state = false; 1799 1800 /* Exit the polling mode, but don't re-enable interrupts if stack might 1801 * poll us due to busy-polling 1802 */ 1803 if (likely(napi_complete_done(napi, work_done))) 1804 iavf_update_enable_itr(vsi, q_vector); 1805 1806 return min_t(int, work_done, budget - 1); 1807 } 1808 1809 /** 1810 * iavf_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW 1811 * @skb: send buffer 1812 * @tx_ring: ring to send buffer on 1813 * @flags: the tx flags to be set 1814 * 1815 * Checks the skb and set up correspondingly several generic transmit flags 1816 * related to VLAN tagging for the HW, such as VLAN, DCB, etc. 1817 * 1818 * Returns error code indicate the frame should be dropped upon error and the 1819 * otherwise returns 0 to indicate the flags has been set properly. 1820 **/ 1821 static void iavf_tx_prepare_vlan_flags(struct sk_buff *skb, 1822 struct iavf_ring *tx_ring, u32 *flags) 1823 { 1824 u32 tx_flags = 0; 1825 1826 1827 /* stack will only request hardware VLAN insertion offload for protocols 1828 * that the driver supports and has enabled 1829 */ 1830 if (!skb_vlan_tag_present(skb)) 1831 return; 1832 1833 tx_flags |= skb_vlan_tag_get(skb) << IAVF_TX_FLAGS_VLAN_SHIFT; 1834 if (tx_ring->flags & IAVF_TXR_FLAGS_VLAN_TAG_LOC_L2TAG2) { 1835 tx_flags |= IAVF_TX_FLAGS_HW_OUTER_SINGLE_VLAN; 1836 } else if (tx_ring->flags & IAVF_TXRX_FLAGS_VLAN_TAG_LOC_L2TAG1) { 1837 tx_flags |= IAVF_TX_FLAGS_HW_VLAN; 1838 } else { 1839 dev_dbg(tx_ring->dev, "Unsupported Tx VLAN tag location requested\n"); 1840 return; 1841 } 1842 1843 *flags = tx_flags; 1844 } 1845 1846 /** 1847 * iavf_tso - set up the tso context descriptor 1848 * @first: pointer to first Tx buffer for xmit 1849 * @hdr_len: ptr to the size of the packet header 1850 * @cd_type_cmd_tso_mss: Quad Word 1 1851 * 1852 * Returns 0 if no TSO can happen, 1 if tso is going, or error 1853 **/ 1854 static int iavf_tso(struct iavf_tx_buffer *first, u8 *hdr_len, 1855 u64 *cd_type_cmd_tso_mss) 1856 { 1857 struct sk_buff *skb = first->skb; 1858 u64 cd_cmd, cd_tso_len, cd_mss; 1859 union { 1860 struct iphdr *v4; 1861 struct ipv6hdr *v6; 1862 unsigned char *hdr; 1863 } ip; 1864 union { 1865 struct tcphdr *tcp; 1866 struct udphdr *udp; 1867 unsigned char *hdr; 1868 } l4; 1869 u32 paylen, l4_offset; 1870 u16 gso_segs, gso_size; 1871 int err; 1872 1873 if (skb->ip_summed != CHECKSUM_PARTIAL) 1874 return 0; 1875 1876 if (!skb_is_gso(skb)) 1877 return 0; 1878 1879 err = skb_cow_head(skb, 0); 1880 if (err < 0) 1881 return err; 1882 1883 ip.hdr = skb_network_header(skb); 1884 l4.hdr = skb_transport_header(skb); 1885 1886 /* initialize outer IP header fields */ 1887 if (ip.v4->version == 4) { 1888 ip.v4->tot_len = 0; 1889 ip.v4->check = 0; 1890 } else { 1891 ip.v6->payload_len = 0; 1892 } 1893 1894 if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE | 1895 SKB_GSO_GRE_CSUM | 1896 SKB_GSO_IPXIP4 | 1897 SKB_GSO_IPXIP6 | 1898 SKB_GSO_UDP_TUNNEL | 1899 SKB_GSO_UDP_TUNNEL_CSUM)) { 1900 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) && 1901 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) { 1902 l4.udp->len = 0; 1903 1904 /* determine offset of outer transport header */ 1905 l4_offset = l4.hdr - skb->data; 1906 1907 /* remove payload length from outer checksum */ 1908 paylen = skb->len - l4_offset; 1909 csum_replace_by_diff(&l4.udp->check, 1910 (__force __wsum)htonl(paylen)); 1911 } 1912 1913 /* reset pointers to inner headers */ 1914 ip.hdr = skb_inner_network_header(skb); 1915 l4.hdr = skb_inner_transport_header(skb); 1916 1917 /* initialize inner IP header fields */ 1918 if (ip.v4->version == 4) { 1919 ip.v4->tot_len = 0; 1920 ip.v4->check = 0; 1921 } else { 1922 ip.v6->payload_len = 0; 1923 } 1924 } 1925 1926 /* determine offset of inner transport header */ 1927 l4_offset = l4.hdr - skb->data; 1928 /* remove payload length from inner checksum */ 1929 paylen = skb->len - l4_offset; 1930 1931 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) { 1932 csum_replace_by_diff(&l4.udp->check, 1933 (__force __wsum)htonl(paylen)); 1934 /* compute length of UDP segmentation header */ 1935 *hdr_len = (u8)sizeof(l4.udp) + l4_offset; 1936 } else { 1937 csum_replace_by_diff(&l4.tcp->check, 1938 (__force __wsum)htonl(paylen)); 1939 /* compute length of TCP segmentation header */ 1940 *hdr_len = (u8)((l4.tcp->doff * 4) + l4_offset); 1941 } 1942 1943 /* pull values out of skb_shinfo */ 1944 gso_size = skb_shinfo(skb)->gso_size; 1945 gso_segs = skb_shinfo(skb)->gso_segs; 1946 1947 /* update GSO size and bytecount with header size */ 1948 first->gso_segs = gso_segs; 1949 first->bytecount += (first->gso_segs - 1) * *hdr_len; 1950 1951 /* find the field values */ 1952 cd_cmd = IAVF_TX_CTX_DESC_TSO; 1953 cd_tso_len = skb->len - *hdr_len; 1954 cd_mss = gso_size; 1955 *cd_type_cmd_tso_mss |= (cd_cmd << IAVF_TXD_CTX_QW1_CMD_SHIFT) | 1956 (cd_tso_len << IAVF_TXD_CTX_QW1_TSO_LEN_SHIFT) | 1957 (cd_mss << IAVF_TXD_CTX_QW1_MSS_SHIFT); 1958 return 1; 1959 } 1960 1961 /** 1962 * iavf_tx_enable_csum - Enable Tx checksum offloads 1963 * @skb: send buffer 1964 * @tx_flags: pointer to Tx flags currently set 1965 * @td_cmd: Tx descriptor command bits to set 1966 * @td_offset: Tx descriptor header offsets to set 1967 * @tx_ring: Tx descriptor ring 1968 * @cd_tunneling: ptr to context desc bits 1969 **/ 1970 static int iavf_tx_enable_csum(struct sk_buff *skb, u32 *tx_flags, 1971 u32 *td_cmd, u32 *td_offset, 1972 struct iavf_ring *tx_ring, 1973 u32 *cd_tunneling) 1974 { 1975 union { 1976 struct iphdr *v4; 1977 struct ipv6hdr *v6; 1978 unsigned char *hdr; 1979 } ip; 1980 union { 1981 struct tcphdr *tcp; 1982 struct udphdr *udp; 1983 unsigned char *hdr; 1984 } l4; 1985 unsigned char *exthdr; 1986 u32 offset, cmd = 0; 1987 __be16 frag_off; 1988 u8 l4_proto = 0; 1989 1990 if (skb->ip_summed != CHECKSUM_PARTIAL) 1991 return 0; 1992 1993 ip.hdr = skb_network_header(skb); 1994 l4.hdr = skb_transport_header(skb); 1995 1996 /* compute outer L2 header size */ 1997 offset = ((ip.hdr - skb->data) / 2) << IAVF_TX_DESC_LENGTH_MACLEN_SHIFT; 1998 1999 if (skb->encapsulation) { 2000 u32 tunnel = 0; 2001 /* define outer network header type */ 2002 if (*tx_flags & IAVF_TX_FLAGS_IPV4) { 2003 tunnel |= (*tx_flags & IAVF_TX_FLAGS_TSO) ? 2004 IAVF_TX_CTX_EXT_IP_IPV4 : 2005 IAVF_TX_CTX_EXT_IP_IPV4_NO_CSUM; 2006 2007 l4_proto = ip.v4->protocol; 2008 } else if (*tx_flags & IAVF_TX_FLAGS_IPV6) { 2009 tunnel |= IAVF_TX_CTX_EXT_IP_IPV6; 2010 2011 exthdr = ip.hdr + sizeof(*ip.v6); 2012 l4_proto = ip.v6->nexthdr; 2013 if (l4.hdr != exthdr) 2014 ipv6_skip_exthdr(skb, exthdr - skb->data, 2015 &l4_proto, &frag_off); 2016 } 2017 2018 /* define outer transport */ 2019 switch (l4_proto) { 2020 case IPPROTO_UDP: 2021 tunnel |= IAVF_TXD_CTX_UDP_TUNNELING; 2022 *tx_flags |= IAVF_TX_FLAGS_VXLAN_TUNNEL; 2023 break; 2024 case IPPROTO_GRE: 2025 tunnel |= IAVF_TXD_CTX_GRE_TUNNELING; 2026 *tx_flags |= IAVF_TX_FLAGS_VXLAN_TUNNEL; 2027 break; 2028 case IPPROTO_IPIP: 2029 case IPPROTO_IPV6: 2030 *tx_flags |= IAVF_TX_FLAGS_VXLAN_TUNNEL; 2031 l4.hdr = skb_inner_network_header(skb); 2032 break; 2033 default: 2034 if (*tx_flags & IAVF_TX_FLAGS_TSO) 2035 return -1; 2036 2037 skb_checksum_help(skb); 2038 return 0; 2039 } 2040 2041 /* compute outer L3 header size */ 2042 tunnel |= ((l4.hdr - ip.hdr) / 4) << 2043 IAVF_TXD_CTX_QW0_EXT_IPLEN_SHIFT; 2044 2045 /* switch IP header pointer from outer to inner header */ 2046 ip.hdr = skb_inner_network_header(skb); 2047 2048 /* compute tunnel header size */ 2049 tunnel |= ((ip.hdr - l4.hdr) / 2) << 2050 IAVF_TXD_CTX_QW0_NATLEN_SHIFT; 2051 2052 /* indicate if we need to offload outer UDP header */ 2053 if ((*tx_flags & IAVF_TX_FLAGS_TSO) && 2054 !(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) && 2055 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) 2056 tunnel |= IAVF_TXD_CTX_QW0_L4T_CS_MASK; 2057 2058 /* record tunnel offload values */ 2059 *cd_tunneling |= tunnel; 2060 2061 /* switch L4 header pointer from outer to inner */ 2062 l4.hdr = skb_inner_transport_header(skb); 2063 l4_proto = 0; 2064 2065 /* reset type as we transition from outer to inner headers */ 2066 *tx_flags &= ~(IAVF_TX_FLAGS_IPV4 | IAVF_TX_FLAGS_IPV6); 2067 if (ip.v4->version == 4) 2068 *tx_flags |= IAVF_TX_FLAGS_IPV4; 2069 if (ip.v6->version == 6) 2070 *tx_flags |= IAVF_TX_FLAGS_IPV6; 2071 } 2072 2073 /* Enable IP checksum offloads */ 2074 if (*tx_flags & IAVF_TX_FLAGS_IPV4) { 2075 l4_proto = ip.v4->protocol; 2076 /* the stack computes the IP header already, the only time we 2077 * need the hardware to recompute it is in the case of TSO. 2078 */ 2079 cmd |= (*tx_flags & IAVF_TX_FLAGS_TSO) ? 2080 IAVF_TX_DESC_CMD_IIPT_IPV4_CSUM : 2081 IAVF_TX_DESC_CMD_IIPT_IPV4; 2082 } else if (*tx_flags & IAVF_TX_FLAGS_IPV6) { 2083 cmd |= IAVF_TX_DESC_CMD_IIPT_IPV6; 2084 2085 exthdr = ip.hdr + sizeof(*ip.v6); 2086 l4_proto = ip.v6->nexthdr; 2087 if (l4.hdr != exthdr) 2088 ipv6_skip_exthdr(skb, exthdr - skb->data, 2089 &l4_proto, &frag_off); 2090 } 2091 2092 /* compute inner L3 header size */ 2093 offset |= ((l4.hdr - ip.hdr) / 4) << IAVF_TX_DESC_LENGTH_IPLEN_SHIFT; 2094 2095 /* Enable L4 checksum offloads */ 2096 switch (l4_proto) { 2097 case IPPROTO_TCP: 2098 /* enable checksum offloads */ 2099 cmd |= IAVF_TX_DESC_CMD_L4T_EOFT_TCP; 2100 offset |= l4.tcp->doff << IAVF_TX_DESC_LENGTH_L4_FC_LEN_SHIFT; 2101 break; 2102 case IPPROTO_SCTP: 2103 /* enable SCTP checksum offload */ 2104 cmd |= IAVF_TX_DESC_CMD_L4T_EOFT_SCTP; 2105 offset |= (sizeof(struct sctphdr) >> 2) << 2106 IAVF_TX_DESC_LENGTH_L4_FC_LEN_SHIFT; 2107 break; 2108 case IPPROTO_UDP: 2109 /* enable UDP checksum offload */ 2110 cmd |= IAVF_TX_DESC_CMD_L4T_EOFT_UDP; 2111 offset |= (sizeof(struct udphdr) >> 2) << 2112 IAVF_TX_DESC_LENGTH_L4_FC_LEN_SHIFT; 2113 break; 2114 default: 2115 if (*tx_flags & IAVF_TX_FLAGS_TSO) 2116 return -1; 2117 skb_checksum_help(skb); 2118 return 0; 2119 } 2120 2121 *td_cmd |= cmd; 2122 *td_offset |= offset; 2123 2124 return 1; 2125 } 2126 2127 /** 2128 * iavf_create_tx_ctx - Build the Tx context descriptor 2129 * @tx_ring: ring to create the descriptor on 2130 * @cd_type_cmd_tso_mss: Quad Word 1 2131 * @cd_tunneling: Quad Word 0 - bits 0-31 2132 * @cd_l2tag2: Quad Word 0 - bits 32-63 2133 **/ 2134 static void iavf_create_tx_ctx(struct iavf_ring *tx_ring, 2135 const u64 cd_type_cmd_tso_mss, 2136 const u32 cd_tunneling, const u32 cd_l2tag2) 2137 { 2138 struct iavf_tx_context_desc *context_desc; 2139 int i = tx_ring->next_to_use; 2140 2141 if ((cd_type_cmd_tso_mss == IAVF_TX_DESC_DTYPE_CONTEXT) && 2142 !cd_tunneling && !cd_l2tag2) 2143 return; 2144 2145 /* grab the next descriptor */ 2146 context_desc = IAVF_TX_CTXTDESC(tx_ring, i); 2147 2148 i++; 2149 tx_ring->next_to_use = (i < tx_ring->count) ? i : 0; 2150 2151 /* cpu_to_le32 and assign to struct fields */ 2152 context_desc->tunneling_params = cpu_to_le32(cd_tunneling); 2153 context_desc->l2tag2 = cpu_to_le16(cd_l2tag2); 2154 context_desc->rsvd = cpu_to_le16(0); 2155 context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss); 2156 } 2157 2158 /** 2159 * __iavf_chk_linearize - Check if there are more than 8 buffers per packet 2160 * @skb: send buffer 2161 * 2162 * Note: Our HW can't DMA more than 8 buffers to build a packet on the wire 2163 * and so we need to figure out the cases where we need to linearize the skb. 2164 * 2165 * For TSO we need to count the TSO header and segment payload separately. 2166 * As such we need to check cases where we have 7 fragments or more as we 2167 * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for 2168 * the segment payload in the first descriptor, and another 7 for the 2169 * fragments. 2170 **/ 2171 bool __iavf_chk_linearize(struct sk_buff *skb) 2172 { 2173 const skb_frag_t *frag, *stale; 2174 int nr_frags, sum; 2175 2176 /* no need to check if number of frags is less than 7 */ 2177 nr_frags = skb_shinfo(skb)->nr_frags; 2178 if (nr_frags < (IAVF_MAX_BUFFER_TXD - 1)) 2179 return false; 2180 2181 /* We need to walk through the list and validate that each group 2182 * of 6 fragments totals at least gso_size. 2183 */ 2184 nr_frags -= IAVF_MAX_BUFFER_TXD - 2; 2185 frag = &skb_shinfo(skb)->frags[0]; 2186 2187 /* Initialize size to the negative value of gso_size minus 1. We 2188 * use this as the worst case scenerio in which the frag ahead 2189 * of us only provides one byte which is why we are limited to 6 2190 * descriptors for a single transmit as the header and previous 2191 * fragment are already consuming 2 descriptors. 2192 */ 2193 sum = 1 - skb_shinfo(skb)->gso_size; 2194 2195 /* Add size of frags 0 through 4 to create our initial sum */ 2196 sum += skb_frag_size(frag++); 2197 sum += skb_frag_size(frag++); 2198 sum += skb_frag_size(frag++); 2199 sum += skb_frag_size(frag++); 2200 sum += skb_frag_size(frag++); 2201 2202 /* Walk through fragments adding latest fragment, testing it, and 2203 * then removing stale fragments from the sum. 2204 */ 2205 for (stale = &skb_shinfo(skb)->frags[0];; stale++) { 2206 int stale_size = skb_frag_size(stale); 2207 2208 sum += skb_frag_size(frag++); 2209 2210 /* The stale fragment may present us with a smaller 2211 * descriptor than the actual fragment size. To account 2212 * for that we need to remove all the data on the front and 2213 * figure out what the remainder would be in the last 2214 * descriptor associated with the fragment. 2215 */ 2216 if (stale_size > IAVF_MAX_DATA_PER_TXD) { 2217 int align_pad = -(skb_frag_off(stale)) & 2218 (IAVF_MAX_READ_REQ_SIZE - 1); 2219 2220 sum -= align_pad; 2221 stale_size -= align_pad; 2222 2223 do { 2224 sum -= IAVF_MAX_DATA_PER_TXD_ALIGNED; 2225 stale_size -= IAVF_MAX_DATA_PER_TXD_ALIGNED; 2226 } while (stale_size > IAVF_MAX_DATA_PER_TXD); 2227 } 2228 2229 /* if sum is negative we failed to make sufficient progress */ 2230 if (sum < 0) 2231 return true; 2232 2233 if (!nr_frags--) 2234 break; 2235 2236 sum -= stale_size; 2237 } 2238 2239 return false; 2240 } 2241 2242 /** 2243 * __iavf_maybe_stop_tx - 2nd level check for tx stop conditions 2244 * @tx_ring: the ring to be checked 2245 * @size: the size buffer we want to assure is available 2246 * 2247 * Returns -EBUSY if a stop is needed, else 0 2248 **/ 2249 int __iavf_maybe_stop_tx(struct iavf_ring *tx_ring, int size) 2250 { 2251 netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index); 2252 /* Memory barrier before checking head and tail */ 2253 smp_mb(); 2254 2255 /* Check again in a case another CPU has just made room available. */ 2256 if (likely(IAVF_DESC_UNUSED(tx_ring) < size)) 2257 return -EBUSY; 2258 2259 /* A reprieve! - use start_queue because it doesn't call schedule */ 2260 netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index); 2261 ++tx_ring->tx_stats.restart_queue; 2262 return 0; 2263 } 2264 2265 /** 2266 * iavf_tx_map - Build the Tx descriptor 2267 * @tx_ring: ring to send buffer on 2268 * @skb: send buffer 2269 * @first: first buffer info buffer to use 2270 * @tx_flags: collected send information 2271 * @hdr_len: size of the packet header 2272 * @td_cmd: the command field in the descriptor 2273 * @td_offset: offset for checksum or crc 2274 **/ 2275 static void iavf_tx_map(struct iavf_ring *tx_ring, struct sk_buff *skb, 2276 struct iavf_tx_buffer *first, u32 tx_flags, 2277 const u8 hdr_len, u32 td_cmd, u32 td_offset) 2278 { 2279 unsigned int data_len = skb->data_len; 2280 unsigned int size = skb_headlen(skb); 2281 skb_frag_t *frag; 2282 struct iavf_tx_buffer *tx_bi; 2283 struct iavf_tx_desc *tx_desc; 2284 u16 i = tx_ring->next_to_use; 2285 u32 td_tag = 0; 2286 dma_addr_t dma; 2287 2288 if (tx_flags & IAVF_TX_FLAGS_HW_VLAN) { 2289 td_cmd |= IAVF_TX_DESC_CMD_IL2TAG1; 2290 td_tag = FIELD_GET(IAVF_TX_FLAGS_VLAN_MASK, tx_flags); 2291 } 2292 2293 first->tx_flags = tx_flags; 2294 2295 dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE); 2296 2297 tx_desc = IAVF_TX_DESC(tx_ring, i); 2298 tx_bi = first; 2299 2300 for (frag = &skb_shinfo(skb)->frags[0];; frag++) { 2301 unsigned int max_data = IAVF_MAX_DATA_PER_TXD_ALIGNED; 2302 2303 if (dma_mapping_error(tx_ring->dev, dma)) 2304 goto dma_error; 2305 2306 /* record length, and DMA address */ 2307 dma_unmap_len_set(tx_bi, len, size); 2308 dma_unmap_addr_set(tx_bi, dma, dma); 2309 2310 /* align size to end of page */ 2311 max_data += -dma & (IAVF_MAX_READ_REQ_SIZE - 1); 2312 tx_desc->buffer_addr = cpu_to_le64(dma); 2313 2314 while (unlikely(size > IAVF_MAX_DATA_PER_TXD)) { 2315 tx_desc->cmd_type_offset_bsz = 2316 build_ctob(td_cmd, td_offset, 2317 max_data, td_tag); 2318 2319 tx_desc++; 2320 i++; 2321 2322 if (i == tx_ring->count) { 2323 tx_desc = IAVF_TX_DESC(tx_ring, 0); 2324 i = 0; 2325 } 2326 2327 dma += max_data; 2328 size -= max_data; 2329 2330 max_data = IAVF_MAX_DATA_PER_TXD_ALIGNED; 2331 tx_desc->buffer_addr = cpu_to_le64(dma); 2332 } 2333 2334 if (likely(!data_len)) 2335 break; 2336 2337 tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset, 2338 size, td_tag); 2339 2340 tx_desc++; 2341 i++; 2342 2343 if (i == tx_ring->count) { 2344 tx_desc = IAVF_TX_DESC(tx_ring, 0); 2345 i = 0; 2346 } 2347 2348 size = skb_frag_size(frag); 2349 data_len -= size; 2350 2351 dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size, 2352 DMA_TO_DEVICE); 2353 2354 tx_bi = &tx_ring->tx_bi[i]; 2355 } 2356 2357 netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount); 2358 2359 i++; 2360 if (i == tx_ring->count) 2361 i = 0; 2362 2363 tx_ring->next_to_use = i; 2364 2365 iavf_maybe_stop_tx(tx_ring, DESC_NEEDED); 2366 2367 /* write last descriptor with RS and EOP bits */ 2368 td_cmd |= IAVF_TXD_CMD; 2369 tx_desc->cmd_type_offset_bsz = 2370 build_ctob(td_cmd, td_offset, size, td_tag); 2371 2372 skb_tx_timestamp(skb); 2373 2374 /* Force memory writes to complete before letting h/w know there 2375 * are new descriptors to fetch. 2376 * 2377 * We also use this memory barrier to make certain all of the 2378 * status bits have been updated before next_to_watch is written. 2379 */ 2380 wmb(); 2381 2382 /* set next_to_watch value indicating a packet is present */ 2383 first->next_to_watch = tx_desc; 2384 2385 /* notify HW of packet */ 2386 if (netif_xmit_stopped(txring_txq(tx_ring)) || !netdev_xmit_more()) { 2387 writel(i, tx_ring->tail); 2388 } 2389 2390 return; 2391 2392 dma_error: 2393 dev_info(tx_ring->dev, "TX DMA map failed\n"); 2394 2395 /* clear dma mappings for failed tx_bi map */ 2396 for (;;) { 2397 tx_bi = &tx_ring->tx_bi[i]; 2398 iavf_unmap_and_free_tx_resource(tx_ring, tx_bi); 2399 if (tx_bi == first) 2400 break; 2401 if (i == 0) 2402 i = tx_ring->count; 2403 i--; 2404 } 2405 2406 tx_ring->next_to_use = i; 2407 } 2408 2409 /** 2410 * iavf_xmit_frame_ring - Sends buffer on Tx ring 2411 * @skb: send buffer 2412 * @tx_ring: ring to send buffer on 2413 * 2414 * Returns NETDEV_TX_OK if sent, else an error code 2415 **/ 2416 static netdev_tx_t iavf_xmit_frame_ring(struct sk_buff *skb, 2417 struct iavf_ring *tx_ring) 2418 { 2419 u64 cd_type_cmd_tso_mss = IAVF_TX_DESC_DTYPE_CONTEXT; 2420 u32 cd_tunneling = 0, cd_l2tag2 = 0; 2421 struct iavf_tx_buffer *first; 2422 u32 td_offset = 0; 2423 u32 tx_flags = 0; 2424 __be16 protocol; 2425 u32 td_cmd = 0; 2426 u8 hdr_len = 0; 2427 int tso, count; 2428 2429 /* prefetch the data, we'll need it later */ 2430 prefetch(skb->data); 2431 2432 iavf_trace(xmit_frame_ring, skb, tx_ring); 2433 2434 count = iavf_xmit_descriptor_count(skb); 2435 if (iavf_chk_linearize(skb, count)) { 2436 if (__skb_linearize(skb)) { 2437 dev_kfree_skb_any(skb); 2438 return NETDEV_TX_OK; 2439 } 2440 count = iavf_txd_use_count(skb->len); 2441 tx_ring->tx_stats.tx_linearize++; 2442 } 2443 2444 /* need: 1 descriptor per page * PAGE_SIZE/IAVF_MAX_DATA_PER_TXD, 2445 * + 1 desc for skb_head_len/IAVF_MAX_DATA_PER_TXD, 2446 * + 4 desc gap to avoid the cache line where head is, 2447 * + 1 desc for context descriptor, 2448 * otherwise try next time 2449 */ 2450 if (iavf_maybe_stop_tx(tx_ring, count + 4 + 1)) { 2451 tx_ring->tx_stats.tx_busy++; 2452 return NETDEV_TX_BUSY; 2453 } 2454 2455 /* record the location of the first descriptor for this packet */ 2456 first = &tx_ring->tx_bi[tx_ring->next_to_use]; 2457 first->skb = skb; 2458 first->bytecount = skb->len; 2459 first->gso_segs = 1; 2460 2461 /* prepare the xmit flags */ 2462 iavf_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags); 2463 if (tx_flags & IAVF_TX_FLAGS_HW_OUTER_SINGLE_VLAN) { 2464 cd_type_cmd_tso_mss |= IAVF_TX_CTX_DESC_IL2TAG2 << 2465 IAVF_TXD_CTX_QW1_CMD_SHIFT; 2466 cd_l2tag2 = FIELD_GET(IAVF_TX_FLAGS_VLAN_MASK, tx_flags); 2467 } 2468 2469 /* obtain protocol of skb */ 2470 protocol = vlan_get_protocol(skb); 2471 2472 /* setup IPv4/IPv6 offloads */ 2473 if (protocol == htons(ETH_P_IP)) 2474 tx_flags |= IAVF_TX_FLAGS_IPV4; 2475 else if (protocol == htons(ETH_P_IPV6)) 2476 tx_flags |= IAVF_TX_FLAGS_IPV6; 2477 2478 tso = iavf_tso(first, &hdr_len, &cd_type_cmd_tso_mss); 2479 2480 if (tso < 0) 2481 goto out_drop; 2482 else if (tso) 2483 tx_flags |= IAVF_TX_FLAGS_TSO; 2484 2485 /* Always offload the checksum, since it's in the data descriptor */ 2486 tso = iavf_tx_enable_csum(skb, &tx_flags, &td_cmd, &td_offset, 2487 tx_ring, &cd_tunneling); 2488 if (tso < 0) 2489 goto out_drop; 2490 2491 /* always enable CRC insertion offload */ 2492 td_cmd |= IAVF_TX_DESC_CMD_ICRC; 2493 2494 iavf_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss, 2495 cd_tunneling, cd_l2tag2); 2496 2497 iavf_tx_map(tx_ring, skb, first, tx_flags, hdr_len, 2498 td_cmd, td_offset); 2499 2500 return NETDEV_TX_OK; 2501 2502 out_drop: 2503 iavf_trace(xmit_frame_ring_drop, first->skb, tx_ring); 2504 dev_kfree_skb_any(first->skb); 2505 first->skb = NULL; 2506 return NETDEV_TX_OK; 2507 } 2508 2509 /** 2510 * iavf_xmit_frame - Selects the correct VSI and Tx queue to send buffer 2511 * @skb: send buffer 2512 * @netdev: network interface device structure 2513 * 2514 * Returns NETDEV_TX_OK if sent, else an error code 2515 **/ 2516 netdev_tx_t iavf_xmit_frame(struct sk_buff *skb, struct net_device *netdev) 2517 { 2518 struct iavf_adapter *adapter = netdev_priv(netdev); 2519 struct iavf_ring *tx_ring = &adapter->tx_rings[skb->queue_mapping]; 2520 2521 /* hardware can't handle really short frames, hardware padding works 2522 * beyond this point 2523 */ 2524 if (unlikely(skb->len < IAVF_MIN_TX_LEN)) { 2525 if (skb_pad(skb, IAVF_MIN_TX_LEN - skb->len)) 2526 return NETDEV_TX_OK; 2527 skb->len = IAVF_MIN_TX_LEN; 2528 skb_set_tail_pointer(skb, IAVF_MIN_TX_LEN); 2529 } 2530 2531 return iavf_xmit_frame_ring(skb, tx_ring); 2532 } 2533